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Steve Hunter
57,712 PointsMessageAdapter error - cannot cast
Hi all,
I have just added the line of code that reloads the MessageAdapter if it does not already exist:
((MessageAdapter)getListView().getAdapter()).refill(mMessages);
I get an error in LogCat that says:
ClassCastException - android.widget.ArrayAdapter cannot be cast to MessageAdapter
This error is pointing at line 65 of the InboxFragment which is the line of code above.
Any thoughts?
Thanks,
Steve.
5 Answers
Ben Jakuben
Treehouse TeacherOkay, the first thing I notice is that our import statements are different. You aren't importing MessageAdapter, but you are importing ArrayAdapter. Try this:
Delete:
import android.widget.ArrayAdapter;
And add:
import uk.co.bigdogconsultants.ribbit.adapters.MessageAdapter;
(or whatever your package name is)
Ah, and now I see that you are still using an ArrayAdapter instead of MessageAdapter. Change this:
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
getListView().getContext(),
android.R.layout.simple_list_item_1,
usernames);
setListAdapter(adapter);
to this:
MessageAdapter adapter = new MessageAdapter(
getListView().getContext(),
mMessages);
setListAdapter(adapter);
Tom Wierman
3,002 PointsThis works in my project:
import android.support.v4.widget.SwipeRefreshLayout;
} else {
//refill the adapter
((MessageAdapter) getListView().getAdapter()).refill(mMessages);
Steve Hunter
57,712 PointsThat's the same as my code, so the error must lie elsewhere. It's strange as it compiles and build & even runs but fails during runtime with the above error.
Maybe I'll get lucky and Ben Jakuben will have a look!
Ben Jakuben
Treehouse TeacherWhat class is your MessageAdapter extending?
Steve Hunter
57,712 PointsHI Ben,
I've got:
public class MessageAdapter extends ArrayAdapter<ParseObject>{
Steve.
Ben Jakuben
Treehouse TeacherMatches mine! Can you paste in all your code from InboxFragment.java?
Steve Hunter
57,712 PointsThis is the code ...
package uk.co.bigdogconsultants.ribbit;
import java.util.List;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.v4.app.ListFragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import com.parse.FindCallback;
import com.parse.ParseException;
import com.parse.ParseFile;
import com.parse.ParseObject;
import com.parse.ParseQuery;
import com.parse.ParseUser;
public class InboxFragment extends ListFragment {
protected List<ParseObject> mMessages;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_inbox, container, false);
return rootView;
}
@Override
public void onResume() {
super.onResume();
getActivity().setProgressBarIndeterminate(true);
ParseQuery<ParseObject> query = new ParseQuery<ParseObject>(ParseConstants.CLASS_MESSAGES);
query.whereEqualTo(ParseConstants.KEY_RECIPIENT_IDS, ParseUser.getCurrentUser().getObjectId());
query.addDescendingOrder(ParseConstants.KEY_CREATED_AT);
query.findInBackground(new FindCallback<ParseObject>() {
@Override
public void done(List<ParseObject> messages, ParseException e) {
getActivity().setProgressBarIndeterminateVisibility(false);
if(e == null) {
// we found messages
mMessages = messages;
String[] usernames = new String[mMessages.size()];
int i = 0;
for(ParseObject message : mMessages) {
usernames[i] = message.getString(ParseConstants.KEY_SENDER_NAME);
i++;
}
if(getListView().getAdapter() == null) {
ArrayAdapter<String> adapter = new ArrayAdapter<String>(
getListView().getContext(),
android.R.layout.simple_list_item_1,
usernames);
setListAdapter(adapter);
}
else {
// refresh the adapter
((MessageAdapter)getListView().getAdapter()).refill(mMessages);
}
}
}
});
}
@Override
public void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
ParseObject message = mMessages.get(position);
String messageType = message.getString(ParseConstants.KEY_FILE_TYPE);
ParseFile file = message.getParseFile(ParseConstants.KEY_FILE);
Uri fileUri = Uri.parse(file.getUrl());
if(messageType.equals(ParseConstants.TYPE_IMAGE)) {
// view image
Intent intent = new Intent(getActivity(), ViewImageActivity.class);
intent.setData(fileUri);
startActivity(intent);
}
else {
// view video
Intent intent = new Intent(Intent.ACTION_VIEW, fileUri);
intent.setDataAndType(fileUri, "video/*");
startActivity(intent);
}
}
}
Thanks,
Steve.
Steve Hunter
57,712 PointsThat all works much better - I don't get an error now. Thanks, Ben :)
However, the Inbox items have no name next to them and the image disappears quickly. I may be confusing the iOS app & the Android one, but I didn't think we'd done the self-destruct yet!! (And my iOS app shows the recipient, not the sender!!)
Steve.
Ben Jakuben
Treehouse TeacherDoh! Take a shot at troubleshooting it and then post any follow-up questions in here. :)